The Serpent Garden is a great book. But it is absolutely not a romance novel.

The definition of the term "romance novel" can be controversial and confusing so before going any further let me define what I mean. I tend to go by the Romance Writers of America definition: if it has "a central love story and an emotionally satisfying and optimistic ending," it's a romance novel.

They don't even have to be books. For example, the foul-mouthed superhero movie Deadpool is 100% a romance novel. So is the freaky South Korean thriller The Handmaiden.

And plenty of stories that everyone thinks of as romantic are not actually romance novels.

It can be epic and star-crossed and squeeze your heartstrings with such violence you want to throw up, but if it ends badly, it ain't a romance.

Usually, when something is mis-classified as romance, it is because it fails the happyish-ending test. Think Gone With the Wind and Wuthering Heights and Romeo and Juliet - all great love stories, none of them romances.

But the Serpent Garden is not disqualified on the basis of its ending.

The problem is that its love story is not, to my way of thinking, central to the plot.

The story is mostly about Susanna Dallet, a young widow who, in trying to make a living by painting after the death of her husband, unwittingly finds herself at the center of a complex web of intrigue surrounding an apocryphal book of demonic secrets on which the fortunes of the royal courts of two countries, a battle between good and evil, and the outcome of an Opus-Dei like occultist conspiracy all ride.

Not that Susanna notices.

She's much more concerned with getting her colors right and not being exposed as the true artist behind a series of pseudo-pornographic religious paintings and finding clients who will actually advance her enough money to keep her household in vellum to realize that the future of two empires hinge on the raw material of her paintings.

Sure, yes, somewhere in there Susanna comes to rather likes this one fellow with sensitive eyes who comes to like her back. And sure, near the end of the book, after many misunderstandings and prolonged absences, they fall in love and marry.

But that does not make this a romance novel.

What's confusing is that it is not in disguised as one either.

Ms. Merkle Riley does not appear to have thought she was writing a romance novel. Her style is unmistakably literary - passages could be lifted and plopped wholesale directly into Wolf Hall and I doubt anyone would know the difference except Hilary Mantel. There are at least ten POV characters, whereas historical romances tend to have no more than three. There are no sex scenes. And it is much longer than your typical genre romance.

Sometimes, for the sake of amping up a book's potential commercial appeal, publishers will attempt to give the trappings of a romance novel to a book that is not really a romance novel. (See: the oeuvre of Curtis Sittenfeld.) But in this case, the cover boasts neither the pink of chick lit nor the pirate shirts and clenched embraces of historical romance. My copy has a Flemish-style portrait, exactly as you would expect from a work of historical fiction about a Flemish-style portraitist.

So is it the readers who have deemed this book a romance? And if so, why?

The most obvious answer would be that the romance arc is just SO GOOD that despite not being central it rises above the other aspects of the book and comes to define it.

But personally, I didn't find the love story particularly special.

Susanna's love interest, Robert Ashton, while a nuanced and sympathetic character, is not a particularly appealing romantic hero. He spends most of the book mistrusting Susanna for the mistaken belief that she conspired to kill her first husband. He is sulky and poor and slightly bad at his job, always getting himself sent away on long missions or getting lost at sea. He is not introduced until the second act of the book and is not around much, so our glimpses of his growing fondness for Susanna are few and far between. And when he does finally profess his love for her he prioritizes getting his boss' permission to marry her over putting a ring on it, to her consternation and, frankly, mine. (GET WITH THE PROGRAM, MASTER ASHTON.)

I really liked this book and would recommend it. It is droll and clever and full of interesting historical detail and wisecracking demons and great lines. It is kind of like Wolf Hall crossed with The Goldfinch.